I also work in the same field at a very large company and can tell you that there is a tremendous amount of time wasted by project mangagers sitting in meetings. I'm well aware of how things are supposed to work.
I have been both the one developing the software and the one managing the process. I go to those meetings - problem is they are not unnecessary - they are used to manage the customer's and company's ever changing expectations and needs - somebody has to do it and the magic is keeping the meeting people happy and the developers working - it is not easy - trust me.